The invention relates to an automatic flushing mechanism and particularly to the automatic dilution and evacuation of urinals installed in a vacuum collection system.
Vacuum collection, or sewer, systems afford attractive advantages over gravity collection, holding, and transfer systems, particularly for shipboard applications where weight constraints are restrictive. Vacuum systems require significantly reduced volumes of flush water, require little space, can be designed to use substantially smaller and lighter piping, and result in both smaller and lighter holding tank facilities and longer periods of independence from shore support.
Existing vacuum urinals require manually operated reduced-volume flushometers to deposit a measured amount of water into the urinal. This triggers a pressure switch that diverts system vacuum through a discharge timing controller to open the flow line discharge valve for an interval of time sufficient to evacuate the line. Flushing is frequently neglected because water does not stand visibly in the bowls of vacuum flush urinals. In addition, flushometers in heavy usage environments, such as Navy ships, require excessive maintenance. As a result volumes of flushing water are often inadequate to prevent offensive odors and scale buildup in the soil drain lines of the system. The required corrective maintenance, either acid cleaning or hydroblasting, is expensive and time-consuming, and generally entails shore-based facilities and support. Laboratory studies indicate that a minimum volumetric flushing water-to-urine dilution ratio of about 1.5 will prevent soil drain line scaling.
It is therefore an object of this invention to provide a means whereby urinals which are part of a vacuum collection system will be automatically flushed by the deposit of a measured amount of water after a predetermined amount of urine has passed through the urinal.
It is further an object to provide vacuum collection system urinals with an automatic flushing capability to reduce scale buildup in soil drain pipes and reduce associated odors and maintenance.
Other objects, advantages and novel features of the invention will become apparent from the following detained description of the invention when considered in conjunction with the accompanying drawings wherein: